Background: Diabetes and hypertension is affecting at an alarming rate in both rural and urban populations in India and very few studies had been carried out among the tribal population. Objective: To determine the prevalence rate of type 2 diabetes mellitus and hypertension and its associated risk factors among the tribal population in Salem District in Tamil Nadu. Materials and Methods: A total of about 525 tribal population above 40 years of age from various tribal places in Yercaud. All of them were screened for diabetes, by checking the random blood glucose levels and blood pressure, body mass index, dietary patterns, and physical activity levels were also recorded. Their knowledge about diabetes was also assessed by a set of 10 questions. Results: Among the study population, people who had RBS ΃ 200 was 28 (male = 11 and female = 17) and between 140 and 200 were 39 (male = 18 and female = 21) and people whose were in the prehypertensive stage was 185 (males 92 and female 93) and people in the stage 1 hypertension was 102 (male = 47 and female = 54) and in stage 2 hypertension was 64 (male = 33 and female = 29). The co-morbidity (diabetes and hypertension) was present in among 45 (male = 25 and female = 20). Among the study population only 1 was obese and 39 were overweight. Among the various risk factors smoking, alcohol and positive family history were found to have a statistical significant association for males whereas among females only the family history was found to have a statistically significant association for both diabetes and hypertension. The knowledge of diabetes among the study population was very poor. None of them were aware about the normal levels of blood sugar and the risk factors. Conclusion: The study documented that the prevalence of diabetes and hypertension is increasingly high in the tribal areas and their awareness levels were very poor.

Keywords: Diabetes, hypertension, prevalence, tribal

How to cite this article:Radhakrishnan S, Ekambaram M. Prevalence of diabetes and hypertension among a tribal population in Tamil Nadu. Arch Med Health Sci 2015;3:66-71

How to cite this URL:Radhakrishnan S, Ekambaram M. Prevalence of diabetes and hypertension among a tribal population in Tamil Nadu. Arch Med Health Sci [serial online] 2015 [cited 2019 May 25];3:66-71. Available from: http://www.amhsjournal.org/text.asp?2015/3/1/66/154948

Introduction

In spite of incredible progress in the field of medicine, curative and preventive health measures, there is still a huge number of population living in isolation in natural and unpolluted surroundings far away from civilization with their traditional values, customs, beliefs and myths intact. They are commonly known as "tribals" and are considered to be the autochthonous people of the land. About half of the world's autochthonous people, comprising 635 tribal communities including 75 primitive tribal communities live in India. The tribal community makes up about 7% of India's population. [1] They thus constitute a substantial portion of our population. Yet, they are ignored by our policy makers.

Today, the uncontrolled way of life is the root cause of all sorts of miseries and many ill-fated diseases to mankind. [2] Diabetes mellitus, a predictable and preventable metabolic disorder is becoming a global epidemic. It is predicted that the diabetes incidence will be doubled in most nations within 20 years and 19% world's diabetic cases are Indians. The etiologies of both these diseases are multi-factorial in nature. Hypertension and diabetes are important risk factors for cardiovascular disease. Given the increasing rates of coronary artery disease among Indians, especially at a younger age, understanding and successfully managing hypertension and diabetes may hold the key to reduce cardiovascular mortality in India. [3] Diabetes and hypertension are also known to coexist in patients. The prevalence of hypertension is 1.5-2.0 times more in those with diabetes than in those without diabetes, whereas almost one-third of the patients with hypertension develop diabetes later. This coexistence presents an increased risk and can accelerate vascular complications. Diabetes and hypertension are manageable health conditions and can be controlled by medicinal interventions, exercises, and balanced diet.

Moreover, detection of progenitors - prediabetes and prehypertension - through periodic surveillance can allow for early intervention and delay disease progression. Studies on diabetes prevalence had shown that around 6-12% in urban and 2-3% in rural Indian populations [4] is diabetic. An accelerated increase of diabetes is also noticed in tribal (or) aboriginal populations worldwide, but very few studies had been done in hilly tribes of India. Hence, this study was carried out to assess the prevalence and the risk factors of diabetes and hypertension in a tribal area in Tamil Nadu.

Materials and Methods

Yercaud is a hill station located from about 25 km from Salem. In Yercaud, there are about 25 tribal villages. Vinayaka Mission Medical College Hospital conducts a routine general camp in Kombuthuki on every Wednesdays. Keeping the prevalence of hypertension and diabetes as 30% and the maximum allowable error as 12% we calculated the sample size, which came to around 425 and to still more improve the validity we added another 100 to the sample and the total study population was made to 525. All the study samples were recruited from the nearby villages namely Vazhavandhi, Kombuthuki, Koravankadu and Mamalaburam by applying a simple random technique for the people aged 40 years and above. Among them, 306 were females and 219 were males. All of them were screened for diabetes, by random blood glucose levels. Along with random blood sugar (RBS), their blood pressure, body mass index (BMI), dietary patterns and physical activity levels were also recorded. Their knowledge about diabetes was also assessed by a set of 10 questions. Based on RBS, the cut-off values were fixed as sugar level ≥200 are considered as diabetic and sugar levels between 140 and 200 are considered to be prediabetic and sugar level <140 is normal. Hypertension was categorized based on JNC seven classification. [5]

Results

[Table 1] shows the distribution of the study population based on the age and gender. Of the total 525 study population, 306 were females and 219 are males. Majority of them were in the age group of between 30 and 60 years. [Table 2] shows the distribution of the study population based on their RBS levels. It is seen from the table that about 18 (8.2%) males and 21 (6.8%) females are in the stage of prediabetic and 11 (5%) males and 17 (5.5%) females were diagnosed as diabetes. Majority of prediabetics (RBS between 140 and 200) and diabetics (RBS >200) were in the age group between 40 and 60 years.

[Table 3] shows the classification of hypertension among the study population. It is seen from the table that about 42% males and 30% females were in the stage of prehypertension and around 36% males and 26% females are diagnosed as hypertensives. Similar to the diabetic prevalence hypertension also found to be more prevalent among the age group between 40 and 60 years and [Table 4] shows that 11.4% males and 6.5% females had both diabetes and hypertension.

[Table 5] shows the various risk factors for diabetes among the study population and from the table it is seen that for males smoking, alcohol consumption and family history of diabetes were found to have statistically significant association for diabetes were as in females the family history of diabetes alone had a statistically significant association and from [Table 6] among the various risk factors for hypertension in males smoking and family history of hypertension was found to have a statistically significant association for developing hypertension and among females the positive family history alone was found to have a statistically significant association.

[Table 5] and [Table 6] show that BMI did not had a statistically significant association for both diabetes and hypertension, whereas most of the studies done in urban and rural areas had shown BMI as a very strong predictor in developing diabetes and hypertension.

The awareness level about diabetes was assessed by a set of 10 questions and that was administered to all the patients and none of them were able to answer any of the questions and the awareness level was almost 0%.

Discussion

The prevalence of diabetes among different sexes is a controversial one. Many earlier studies reveal the male sex specific [6],[7],[8] female sex specific [9],[10] and sex nonspecific [11] prevalence of diabetes. Female sex specific (1.6% in females and 0.8% in males) prevalence of diabetes has been noticed in a recent study done by Murugan and Beula [3] in the tribal areas of Kanyakumari and a study by Sachdev B [12] among the tribal population, showed that the prevalence was 9.8% and 12.5%, respectively with higher prevalence among female population when compared with male population, whereas in this study the prevalence of diabetes was 5 and 5.5% among males and females respectively, which had shown there was no gender specificity among the diabetes prevalence.

Several studies are in support of age - specific onset of type 2 diabetes mellitus (T2DM). [13],[14] The minimum and the maximum age of the diabetic subjects are 51 and 88 years respectively and in our study most of the diabetics were in the age group of between 40 and 60 years, which was in par with the previous studies.

Obesity (or) weight gain is a major risk factor for T2DM. The relationship between BMI and diabetes mellitus is reported by many researchers, [15],[16] whereas in our study, obesity was not a factor to be associated with diabetes and most of our study population were having normal BMI and some were even undernourished. The reason for this was their food habits and the physical activity. Most of them usually have only two meals per day and they walk about 5-7 km/day.

The impacts of alcohol and smoking on diabetes have been discussed by many studies [17],[18] and it was found to be same in our study particularly among males. Family history of diabetes [19] was found to be a strong factor in both males and females among the various other factors, which influences the prevalence of diabetes and the findings is in par with various other studies.

A study carried out by Kokiwar and Gupta [20] using the JNC seven criteria for assessment of hypertension among the age group 30 years and above found the prevalence of hypertension was 19.04% in the rural population of central India. The prevalence of hypertension in rural areas of Tamil Nadu in the age group of 45-60 years was 33%. [21] Although Gupta etal. [22] reported a prevalence of 24% in males and 17% in females in the age group of 20 years and above from rural Rajasthan. Gilberts etal. [23] carried out a study in rural Tamil Nadu in the age group of 20 years and above and found a prevalence of 12.5%, whereas in our study about 42% males and 30% females were in the stage of prehypertension and 36% males and 26% females are hypertensives. The prevalence of population having both diabetes and hypertension as a co-morbid disease was 11.5% in males and 6.5% among females.

Prevalence of hypertension was significantly higher in males than females. Similar findings were reported by Gupta et al. [22] and Dong et al. [24] but Hazarika et al.[25] and Malhotra et al. [26] showed increased prevalence in females when compared with males. All the studies agree with the fact that prevalence of hypertension increased with age [21],[24] which is in par with this study. Age probably represents an accumulation of environmental influences and the effect of genetically programmed senescence in body systems. [27]

A study done by Bansal et al. [28] had shown that both males and females, age and high BMI were significant predictors of hypertension and similar results were also quoted by Gupta et al. [29] whereas in our study smoking was the only modifiable risk factor, which had shown significant association with hypertension and the family history of hypertension, which was a nonmodifiable risk factor had also shown a statistical significant association for hypertension in both males and females.

Conclusion

The two giant chronic morbidities diabetes and hypertension now a pandemic is a new challenge to the modern world. The prevalence usually vary from nation-to-nation, area to area, people to people and even in the same group people. The heterogeneous (or) differential prevalence among people is decided by their socioeconomic, cultural, and topographical conditions. A low level of prevalence of T2DM in the present tribe may be due to their lifestyle changes and genetic constitution, whereas the prevalence of hypertension did not show much difference when compared with urban or rural population. Further studies are required to assess the prevalence, determinants and preventive interventions for diabetes and hypertension in tribal areas. There is a need for strengthening health education programs to promote chronic diseases awareness and emphasize preventive measures among this helpless tribal population.

Subburam R, Sankarapandian M, Gopinath DR, Selvarajan SK, Kabilan L. Prevalence of hypertension and correlates among adults of 45-60 years in a rural area of Tamil Nadu. Indian J Public Health 2009;53:37-40. [PUBMED]

Gilberts EC, Arnold MJ, Grobbee DE. Hypertension and determinants of blood pressure with special reference to socioeconomic status in a rural south Indian community. J Epidemiol Community Health 1994;48:258-61.